Have you ever wished you had special powers, say the ability to leap tall buildings or X-ray vision? Most of us have had such daydreams, but this only happens in comic books. Right?
Well, scientists are learning different, and you might be surprised just who has these special powers.
The parakeet softly chattering in the bird cage in the corner and the kestrel sitting patiently on the utility line outside can do things you and I can't imagine.
When we look at the world, we see a fantastic array of colors ranging from the bright-red flowers of paintbrush and scarlet warriors to the greens of a mountain forest to the deep blue of Crater Lake. What more could there be to see? Quite a bit actually. What we consider "visible light" is just a narrow slice of the electromagnetic spectrum. There are many other kinds of light out there. We don't see the longer wavelengths of infrared, but we feel it as heat on our skin. A few animals, including rattlesnakes and pythons, can see infrared. The pits on their face are a primitive kind of eye tuned to this wavelength. This is quite useful when hunting warm-blooded mammals in the cool of night.
We don't see the shorter wavelengths of ultraviolet light either. However, bees and our parakeet and kestrel see ultraviolet right along with the other colors of the rainbow.
So what are we missing? Well, to humans, male and female parakeets look alike. We formerly thought that parakeets identified each other by differences in behavior. We now know that males and females look quite different. You just need that X-ray — or rather, I should say, ultraviolet — vision.
In case it's been a while since you considered a parakeet, they have a dark spot low on the cheek. Both males and females have this spot. However, the spot of the male shines brightly in ultraviolet light but not the spot of the female. To parakeets, males and females are as different in appearance as male and female quail or tanagers to us. Many other species exhibit similar differences.
Hawks and owls use their "special" vision for other purposes. The urine and droppings of mice and other rodents shine brightly in ultraviolet light. Please don't ask why. I have no idea. However, this is quite useful to a migrating hawk looking for a good territory to raise a family. A quick flight over a field reveals whether the meadow is rich in mice, even if all are safely hidden in their burrows. It hardly seems fair to the mice.
Years ago I studied the diet of great horned owls along the John Day River. Surprisingly, I found they had a passion for scorpions. I should have known. Scorpions shine brightly under ultraviolet light. Apparently there is enough ultraviolet light in the night sky to make scorpions stand out like little crawling light bulbs to one with ultraviolet vision. Who could resist? Not the owls anyway. It makes you wonder just what else we are missing, doesn't it?
Stewart Janes is a biology professor at Southern Oregon University. He can be reached at firstname.lastname@example.org.